81121970 ÷ 159 
We want to divide 81121970 by 159.

Step 1:
If we divide 8 by 159, we get 0 and a remainder of 8.
Use 0 as the next digit of our solution. 
Result so far: 0.0
Deduct 0 from 8 and we're left with 8.
Take the next digit (1) from the dividend and append it to 8, then repeat: 81 / 159

Let's proceed to step 2:
159 can be fit into 81 0 times, resulting in a remainder of 81.
The number 0 becomes the next digit in our result. 
Result so far: 0.0
Deduct 0 from 81 and we're left with 81.
Fetch the next digit (1) from the dividend, attach it to 81 and continue: 811 / 159

Going ahead to step 3:
159 can be fit into 811 5 times, resulting in a remainder of 16.
Record the quotient 5 as the next digit in the result. 
Result so far: 5.0
Deduct 795 from 811 and we're left with 16.
Include the next digit (2) from the dividend after 16, then repeat: 162 / 159

Let's proceed to step 4:
159 goes into 162 1 times with a remainder of 3.
The next digit of our result is 1. 
Result so far: 51.0
If we take 159 away from 162, we end up with 3.
Grab the next digit (1) from the dividend, add it to 3, then carry on: 31 / 159

Moving on to step 5:
The number 159 fits into 31 0 times, leaving a remainder of 31.
The next digit of our result is 0. 
Result so far: 510.0
Deduct 0 from 31 and we're left with 31.
Append the next digit (9) from the dividend to 31 and continue with: 319 / 159

Let's proceed to step 6:
159 can be fit into 319 2 times, resulting in a remainder of 1.
Write down 2 as next digit of the result. 
Result so far: 5102.0
Subtracting 318 from 319 leaves us with 1.
Grab the next digit (7) from the dividend, add it to 1, then carry on: 17 / 159

Moving on to step 7:
159 goes into 17 0 times with a remainder of 17.
The next digit of our result is 0. 
Result so far: 51020.0
Subtracting 0 from 17 leaves us with 17.
Grab the next digit (0) from the dividend, add it to 17, then carry on: 170 / 159

Advancing to step 8:
170 divided by 159 is 1 with a remainder of 11.
Record the quotient 1 as the next digit in the result. 
Result so far: 510201.0
If we take 159 away from 170, we end up with 11.
Since there are no more digits in the dividend, we add a zero to the remainder making it 110, and continue the process.

On to step 9:
159 goes into 110 0 times with a remainder of 110.
Write down 0 as next digit of the result. 
Result so far: 510201.0
The remainder is 110 after subtracting 0 from 110.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1100, and continue the process.

Let's proceed to step 10:
If we divide 1100 by 159, we get 6 and a remainder of 146.
Write down 6 as next digit of the result. 
Result so far: 510201.06
Subtracting 954 from 1100 leaves us with 146.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1460, and continue the process.

Moving on to step 11:
The number 159 fits into 1460 9 times, leaving a remainder of 29.
The next digit of our result is 9. 
Result so far: 510201.069
Subtracting 1431 from 1460 leaves us with 29.
Since there are no more digits in the dividend, we add a zero to the remainder making it 290, and continue the process.

Going ahead to step 12:
If we divide 290 by 159, we get 1 and a remainder of 131.
Put 1 as the next digit of the answer. 
Result so far: 510201.0691
If we subtract 159 from 290, we get 131.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1310, and continue the process.

Step 13:
When dividing 1310 by 159, we get 8 with a remainder of 38.
The number 8 becomes the next digit in our result. 
Result so far: 510201.06918
Subtract 1272 from 1310 to get 38.
Since there are no more digits in the dividend, we add a zero to the remainder making it 380, and continue the process.

Step 14:
If we divide 380 by 159, we get 2 and a remainder of 62.
Use 2 as the next digit of our solution. 
Result so far: 510201.069182
The remainder is 62 after subtracting 318 from 380.
Since there are no more digits in the dividend, we add a zero to the remainder making it 620, and continue the process.

Moving on to step 15:
620 divided by 159 is 3 with a remainder of 143.
The next digit of our result is 3. 
Result so far: 510201.0691823
If we subtract 477 from 620, we get 143.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1430, and continue the process.

Step 16:
159 goes into 1430 8 times with a remainder of 158.
Put 8 as the next digit of the answer. 
Result so far: 510201.06918238
If we take 1272 away from 1430, we end up with 158.
Since there are no more digits in the dividend, we add a zero to the remainder making it 1580, and continue the process.

After the division, we end up with 510201.06918238 and a remainder of 1.58e-07.